1.Context.sensitive half-times of etomidate
Chinese Journal of Postgraduates of Medicine 2011;34(27):1-3
ObjectiveTo investigate the context-sensitive half-times of etomidate. Methods Twenty patients ( ASA Ⅰ - Ⅱ ) underwent selective thoracic operation were divided into 2 groups by random digits table with 10 cases each,the patients were allocated to receive either continuous infusion etomidate 10μg/(kg·min) for 1 h(Gl group) or continuous infusion etomidate 10 μg/(kg·min) for 2 h(G2 group) of maintenance anesthesia. The samples were collected at the following time points: 1 min before stop infusion,2,5, 10,15,20,30,40,50 and 60 min after stop infusion. The plasma concentrations of etomidate were measured by high-performance liquid chromatography and the changes of the context-sensitive half-times of etomidate were calculated. ResultsThe context-sensitive half-times of etomidate was ( 17.1 ± 13.1 )min in G1 group and (21.7 ± 15.1 ) min in G2 group. There was no significant difference between two groups (P>0.05). ConclusionThe context-sensitive half-times of etomidate is short and its pharmacokinetic profile is suitable for continuous infusion.
2.Antibodies and vaccines against glycoprotein of Marburg virus
Li ZHANG ; Qianqian LI ; Weijin HUANG ; Youchun WANG
Chinese Journal of Microbiology and Immunology 2017;37(6):467-473
Marburg virus (MARV) is a lethal virus that causes fatal hemorrhagic fever.It belongs to the Filoviridae family which also includes Ebola virus.MARV is similar to Ebola virus in structure and infection mechanism.Moreover,the diseases caused by them have similar clinical symptoms.However,researches on MARV are less than those on Ebola virus.In this review,we focus on the viral structure,especially the structure of MARV glycoprotein (GP) which determines its infectivity,functions of MARV GP as well as protective antibodies and vaccines against this protein.
3.Evaluation of four domestic and three imported fourth-generation HIV diagnostic reagents
Xiuhua LI ; Sihong XU ; Aijing SONG ; Jianhui NIE ; Youchun. WANG
Chinese Journal of Microbiology and Immunology 2011;31(9):847-850
Objective To evaluate the quality of four domestic and three imported fourth-generation HIV diagnostic reagents.Methods The specificity and sensitivity of these assays were analyzed when testing HIV negative samples and HIV-1 RNA positive samples.The relative seroconversion sensitivity index was analyzed when testing BBI seroconversion panels.Results The sensitivity of seven 4th-generation assays were 100% (95% CI:99.86%-100% ),and one sample at the window period of HIV-1 infection were detected as positive.Of the seven assays,one imported assay exhibited the relative largeδ + value (1.0892),and the small δ+ value were found on the remaining six assays (0.0836-0.3003 ).For the samples negative for HIV antibody,varying degrees of false positives were observed on the seven assays ( specificity:97.80% -99.60%,δ- value:-1.3803 to -0.4778).When testing the BBI seroconversion panels,the relative seroconversion sensitivity index of domestic assays were -0.500-0,however,which of imported assays were -0.600 and -0.700.Conclusion The seven reagents exhibited high sensitivity and specificity.The 4th generation HIV assays can be used as blood screening reagents to find the samples at window period of HIV-1 infection,thus indicating the certain meaning in reducing the transmission risk of HIV-1 for fourth-generation HIV diagnostic reagents.However,the better efficiency to detect HIV-1 early infection was observed on the imported assays than on the domestic assays.
4.Comparative evaluation of eight third generation and four fourth generation anti-HIV diagnostic reagents
Xiuhua LI ; Sihong XU ; Aijing SONG ; Jianhui NIE ; Youchun WANG
Chinese Journal of Microbiology and Immunology 2008;28(10):955-958
Objective To evaluate the differences between the third and the fourth generations of anti-HIV assays,and different kits within the same generation.Methods A total of 989 HIV-negative samples,185 samples positive for HIV-1 RNA.1st-generation international references of HIV antibodies and samples from 9 sets of BBI seroconversion panels were detected by 8 kits of the third generation and 4 kits of the fourth.Results The fourth generation kits can detect HIV infection earlier than the third generation kits.However,the detected days of HIV infection with different kits of the fourth generation were different whilst no significant difierences were found with difierent kits of the third generation.Furthermore,the capacity of detecting samples with different genotypes for different reagents was different,especially the capacity of domestic reagents on detecting HIV-1 O group and HIV-2 samples was relatively weak.Conclusion These data provided information to improve the quality of anti-HIV diagnostic reagents further.
5.Relationship of Helicobacter pyloriin dental plaque with gastric disease
Li SONG ; Wenjie HU ; Zexian JIANG ; Yong XIE ; Youchun WEI
Journal of Practical Stomatology 2000;0(05):-
Objectives: To inveatigate Helicobacter pylo r i (Hp) in dental plaque and its relevance to gastric disease.Methods: 40 physical examination subjects were recruited. Subgingival plaque and gastric biopsy samples were respectively collected for detection of Hpby in vitroculture. Results: Hpwas identified in gastric biopsy from ten of thirty-seven (27.03%) subjects with proven chronic gastric disease. From five of the ten, Hpwas isolated in their dental plaque. None of three subjects without chronic gastric disease had Hpin their gastric bi opsy. However, Hpwas found in dental plaque from one of the three.C onclusion: The results suggest that dental plaque is an ecological niche of Hp. Oral Hpmay be related to chronic gastric disease.
6.Assessment system of research program upgraded
Wanyu ZHANG ; Jun ZHENG ; Jieshou LI ; Youchun YANG ; Shuguang ZHANG ;
Journal of Medical Postgraduates 2003;0(05):-
The authority of hospital administration in charge of the science and technology development will adopt the standard of national evaluation system and implimentation approach into practical regulation.The research projects will be judged by new items including the research objective,demonstration medality,graunds of argument,classification systems,etc. The goal of the new guidelines carried will assure the open and fair policy being practised in examining the adequacy of the research program. The scceessful implimentation of the new rule will encourage the development of highly qualified results achieved in research schemes,and bring about greater social and economic benefits from extensive research work.
7.Primary researches on human genetically engineered antibodies to HIV-1
Sihong XU ; Runlei DU ; Suting WANG ; Aijing SONG ; Xiuhua LI ; Mifang LIANG ; Youchun WANG
Chinese Journal of Microbiology and Immunology 2010;30(11):1057-1062
Objective To pan and characterize anti-HIV-1 Fab by the phage antibody library technology. Methods Total RNA were extracted from lymphocytes which were isolated from peripheral blood collected from asymptomatic HIV-1 infected donors with high titer antibody against HIV-1. The genes of heavy chains Fd fragment and light chains of antibody were amplified by RT-PCR. The phagmids pComb3X cloned Fd and light chain genes were transformed into E. coli XL1-Blue by electroporation to construct phage Fab library. By three runs of "absorption-elution-neutralization-enrichment", the clones were induced by IPTG and characterized by ELISA. The positive clones were sequenced and analyzed the sequences. Subsequently, Fab antibodies of these positive clones were induced to expressed and purified, then the recombinant virus neutralization assay was performed. Results A phage Fab library was constructed with 8×106 members, and 11 positive clones were obtained by detecting IPTG-induced-expressing Fabs with ELISA. By analysis of the sequences, 10 light chain genes and 8 Fd genes were ensured to be obtained. Compared with the genes of anti-HIV-1 antibodies in HIV sequence database, the gene sequences we obtained were highly homologous to some patent genes of anti-HIV-1 gp120 antibodies in HIV sequence database( light chains with 60%-90% identity, Fd with 71%-85% identity); The CDRs of these positive clones were determined by comparing the positive clone genes with antibodies' genes in V base database, furthermore, CDRH3 of these positive clones has the length of 12-22 aa. Strand shift had little effect to improving affinity of our Fab clones. Fab antibodies were induced to express at the concentration of > 10 mg/L. Three Fab antibodies neutralize HIV-1 virus to some extent. Conclusion The studies will provide the basis on further study on the anti-HIV-1 Fabs obtained successfully.
8.Study of the relationship between antibody level and protection induced by human papillomavirus(HPV) L2-peptide
Xueling WU ; Junsheng CUI ; Shufang MENG ; Baowei LI ; Chuntao ZHANG ; Jinping FAN ; Rongguang SHAO ; Youchun WANG
Chinese Journal of Microbiology and Immunology 2010;30(2):159-163
Objective To detect the protection induced by HPV-58 L2 11-200 AA in animal, and analyze the relationship between antibody or neutralizing antibody titers and the protection generated by the immunizmg agent. Methods The peptide of HPV-58 L2 11-200 AA was expressed in E. coli and the mice were immunized with the peptide after purification and adsorption with aluminum adjuvant. The protection provided by different immunizing doses was detected in the mouse model against the challenge of the pseud-ovirions of human papiilomavirus types 58. The total antibodies and neutralizing antibody titers of serum were tested with ELISA and neutralization assay against HPV-58 pseudovirus, respectively. The total antibodies or neutralizing antibody titers that can protect the mouse from infection were analyzed. Results The mice can be protected from the challenge with HPV pseudovirus when the immunizing dose was 8 μg. The neutralizing antibody can not be detected in the immune serum by neutralization assay against pseudovirus. The total anti-body level has a corresponding relationship with the protection showed in mouse model. The results of total antibodies detected by ELISA showed that when the titer of total antibodies was ≥25 000, luminescent signal can not be detected and the mice can be protected from pseudovirus infection. Conclusion HPV-58 L2 11-200 AA peptide can protect mice from pseudovirus infection. L2 peptide has a promising perspective to be a candidate vaccine and the level of total antibodies in the immune serum can be used as a surrogate for the evaluation of protection against HPV infection.
9.STR profiling on authentication of human cell lines for production
Shufang MENG ; Yu WU ; Jianping FENG ; Xueling WU ; Youchun WANG ; Defu LI
Chinese Journal of Microbiology and Immunology 2009;29(7):636-641
Objective To study the application of short tandem repeat (STR) profiling in quality control of human cell lines used for biological production. Methods The methods detecting 9 and 16 STR loci to identify human cell lines by PCR-capiilary electrophoresis were established respectively. Human cell lines, which were derived from many corporations and including diploid cell strains used for virus-vaccine production and 293 cell lines used for gene therapy products, were analyzed and compared by these two methods. Results The STR profiling methods used for authentication of human cell lines were established. Most of human diploid cell strains(20/21 ) used for virus-vaccine production from 13 corporations were iden-tiffed as the intended cells and no cross-contamination was found. However, one MRC-5 cells was identified as a false cell line and one MRC-5 had 3 alleles in D13S317 locus. For 12 strains of 293 cell lines, there were significant differences in STR profiling from different manufactures, which was likely be explained that the sources and gene modifications of these 293 cell lines are not well known and their genes are unstable during passage. Conclusion The STR profiling method has the advantages of high sensitivity and specifici-ty, and can be used for authentication of each of human cell lines for biological production.
10.Detection of hepatitis E virus RNA by real-time fluorescent RT-PCR
Yan YAN ; Chenyan ZHAO ; Zhuo LI ; Jingqin NIU ; Baoshan YAN ; Wa HAO ; Jiming YIN ; Youchun WANG
Chinese Journal of Laboratory Medicine 2009;32(2):175-178
Objective To investigate the clinical significance of detection of hepatitis E virus (HEV) RNA in sera from patients with acute hepatitis E using real-time reverse transcription (RT)-PCR to detect hepatitis E virus RNA in sera from patients with acute hepatitis E.Methods A real-time RT-PCR assay, which can amplifies and detect the conserved region on ORF3, was used in this study. 434 outpatients and hospitalized patients with acute HEV infection was enrolled into this study.Simultaneously,the serum samples from 40 patients with HAV infection, 100 patients with HBV infection and 110 healthy blood donors were collected as the control The real-time RT-PCR was performed to detect HEV RNA in all these sera.Results 232 sera (53.5%) were positive for HEV RNA by real-time RT-PCR and all of the control were negative.The results of real-time RT-PCR and anti-HEV IgM (ELISA) were concordant in 67.1% samples.There was significant difference between the two methods ( Kappa = 0.308, P = 0.000 ).The first serum sample from five serum samples of the patients was positive for HEV RNA and negative for anti-HEV IgM.Follow-up studies showed all the five sera samples were positive for anti-HEV IgM.HEV RNA in serum could be detected between 2 and 10 days.Conclusions The real-time fluorescent RT-PCR method has high specificity, and can be applied to the qualitative detection of the serum with genotypes Ⅰ and Ⅳ of hepatitis E virus.Its clinical use can improve the early diagnosis of HEV.